Anticholinergic Agents Flashcards
What two groups exist as anticholinergics?
1. Muscarinic antagonists aka Parasympatholytic or antimuscarinic Block effects of parasymp. drugs-Atropine, scopolamine 2. Nicotninc antagonists Ganglionic blocker (autonomic NS) Neuromuscular blockers (NMJ) drugs-tetraethylammonium, tubocurarine, succinylcholine
What is a class drug example of a muscarine antagonist?
Atropine
What effects do anticholinergics have on the CNS?
Atropine has minimal effect, scolpalamine is it’s cousin and is used to tx motion sickness, and Parkinson’s (Benztropine)
What effect can toxicity of Scopalamine have on the CNS?
excitation, hallucinations, agitation, coma
What is the effect of anticholinergics on the eye?
mydriasis, loss of accommodation (cycloplegia)
What effect do anticholinergics have on the CV system?
Low dose (0.5-5mg)-blocks M1 and M2 receptors therefore taking away the breaks on M2 and results in Increased BP (because M3 still exists) High Dose (>10mg) total conduction block-death
What effect do anticholinergics have on the resp. system
Bronchodilation, decreased mucus production-tx. for COPD and Asthma
What effect do anticholinergics have on the GI system
Decreased motility, decreased peristalsis, tx. for diarrhea (lomotil)
What effect do anticholinergics have on the GU system
Decrease ability to void-tx for spasms and inflammatory disorders. Contraindicated for pt’s with BPH
What effect do anticholinergics have on the secretory glands?
not always effective because eccrine glands are more sensitive than apocrine glands-but can be used to tx hyperhydrosis.
Name the types of receptors that bind acetylcholine
Muscarinic and nicotinic
Where are cholinergic receptors found in the auto. NS
Postgang parasymp. and ganglionic level in para and sympathetic sides of autonomic NS
What type of neurons release norepinephrine
Adrenergic
A muscarinic agonist causes what effect on the eye?
Constriction
A muscarinic agonist causes what effect on res.
bronchoconstriction
A msucarinic agonist causes what effect on the CV
Decreases HR
A muscarinic agonist causes what effect on GU
stimulates voiding
A muscarinic agonist causes what effect on GI
increases motility
What effect would muscarinic agonist have on the sympathetic portion of the autonomic nervous system?
no effect!
What is the name of the enzyme that metabolized acetylcholine?
AChE
Why do organophosphates inhibit acetylcholinesterase for so long
Covalent bond
What effect does nicotine have on toxic concentrations in humans
Death, seizures, coma, resp. arrest
What effect do anticholinergics have on the Eye Resp GI GU CV
Eye - Belladonna Resp - Bronchodilation GI - Decreased motility GU - Decreased void CV-Low-decreases HR (M1 blocks), Med-increases (M2 and M1 blocks) High-blocks everything
Therapeutic uses of anticholinergics
Tx:
Diarrhea, Urinary spasms, asthma, COPD
What types of pts might anticholinergics be contraindicated
Glaucoma, BPH
Mech action of ganglionic blocking agent
Binds to Nicotinic receptors on para and symp. side of ANS
What is difference between non-depol and depol. muscular blocker
non-depol: Strictly antagonist
Depol: super agonist-stimulates and causes too much action takes away the brakes
Classify as non-depol and deploy Tubercurarine Atracurium Succinylcholine rocuronium coxycurrium veucronium
All are non-depolarizing except succinlycholine
When would someone use a neuromuscular blocking agent
surgery, ICU, mechanical ventillation
